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Variable Structure Control Design for a Magnetic Levitation System
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In this paper the variable structure control theory is utilized to derive a discontinuous controller to the magnetic levitation system. The magnetic levitation system model is considered uncertain, which subjected to the uncertainty in system parameters, also it is open-loop unstable and strongly nonlinear. The proposed variable structure control to magnetic levitation system is proved, and the area of attraction is determined. Additionally, the chattering, which induced due to the discontinuity in control law, is attenuated by using a non-smooth approximate. With this approximation the resulted controller is a continuous variable structure controller with a determined steady state error according to the selected control parameters. Finally the ability and the effectiveness of the proposed continuous variable structure controller to the magnetic levitation system are verified via numerical simulations. When state initiated inside the area of attraction, the results show that the ball position can be directed to follow various desired positions, with steady state error not exceeding .  

 

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Publication Date
Wed Jan 01 2014
Journal Name
Tikrit Journal Of Social Studies And Humanities
A Cultural Window into obituaries of Iraqi Newspapers
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Publication Date
Sun Jun 20 2021
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
SPERGULARIA IRAQENSIS (CARYOPHYLLACEAE), A NEW SPECIES FROM IRAQ
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Spergularia iraqensis sp. nov. is described as a new species from Iraq. This species has been collected from Diyala Province in the central east of Iraq; it is closely related to Spergularia rubra (L.) J. Presl & C. Presl, 1819 and Spergularia bocconei (Scheele) Graebn., 1919.
The distinguishing of the morphological characteristics of the new species alongside the two similar species are discussed with photographs, and an identification key is given for Spergularia iraqensis and other closely related species.

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Publication Date
Wed Jan 01 2020
Journal Name
Journal Of Advanced Research In Dynamical And Control Systems
A surveyon work flow in service oriented systems
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Publication Date
Fri Jan 01 2021
Journal Name
Int. J. Nonlinear Anal. Appl.
Analysis of a harvested discrete-time biological models
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This work aims to analyze a three-dimensional discrete-time biological system, a prey-predator model with a constant harvesting amount. The stage structure lies in the predator species. This analysis is done by finding all possible equilibria and investigating their stability. In order to get an optimal harvesting strategy, we suppose that harvesting is to be a non-constant rate. Finally, numerical simulations are given to confirm the outcome of mathematical analysis.

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Publication Date
Sun Jun 15 2025
Journal Name
الذكوات البيض
Drugs in Iraq 1932-1968 (A Historical Study)
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The spread of drugs in Iraq during the period 1932-1968 was one of the most dangerous. phenomena affecting humans, as it leads to addiction, to the point where people cannot live without it, it also leads to the destruction of the user's nerves and body, and the inability to maintain balance, or even perform daily tasks. There are different types of drugs, and the side effects vary from one type to another However in all cases, drugs remain the scourge of the world, They are a toxic substance that attacks the nerves and tries to destroy them' The importance of the subject lies in the fact that it is anew and unstudied topic, and it studies a phenomenon that affects humanity in general and Iraq in Particular through it light can be shed on t

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Publication Date
Tue Aug 01 2023
Journal Name
Journal Of Engineering
Geomechanics Analysis of Well Drilling Instability: A Review
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Wellbore instability is a significant problem faced during drilling operations and causes loss of circulation, caving, stuck pipe, and well kick or blowout. These problems take extra time to treat and increase the Nonproductive Time (NPT). This paper aims to review the factors that influence the stability of wellbores and know the methods that have been reached to reduce them. Based on a current survey, the factors that affect the stability of the wellbore are far-field stress, rock mechanical properties, natural fractures, pore pressure, wellbore trajectory, drilling fluid chemicals, mobile formations, naturally over-pressured shale collapse, mud weight, temperature, and time. Also, the most suitable ways to reduce well

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Publication Date
Mon Mar 01 2021
Journal Name
Journal Of Physics: Conference Series
A Review on Arabic Sign Language Translator Systems
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Abstract<p>Deaf and dumb peoples are suffering difficulties most of the time in communicating with society. They use sign language to communicate with each other and with normal people. But Normal people find it more difficult to understand the sign language and gestures made by deaf and dumb people. Therefore, many techniques have been employed to tackle this problem by converting the sign language to a text or a voice and vice versa. In recent years, research has progressed steadily in regard to the use of computers to recognize and translate the sign language. This paper reviews significant projects in the field beginning with important steps of sign language translation. These projects can b</p> ... Show More
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Publication Date
Wed May 24 2023
Journal Name
2023 9th International Conference On Information Technology Trends (itt)
A Comparative Study of Unauthorized Drone Detection Techniques
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Publication Date
Mon Mar 01 2021
Journal Name
Iop Conference Series: Materials Science And Engineering
Speech Enhancement Algorithm Based on a Hybrid Estimator
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Abstract<p>Speech is the essential way to interact between humans or between human and machine. However, it is always contaminated with different types of environment noise. Therefore, speech enhancement algorithms (SEA) have appeared as a significant approach in speech processing filed to suppress background noise and return back the original speech signal. In this paper, a new efficient two-stage SEA with low distortion is proposed based on minimum mean square error sense. The estimation of clean signal is performed by taking the advantages of Laplacian speech and noise modeling based on orthogonal transform (Discrete Krawtchouk-Tchebichef transform) coefficients distribution. The Discrete Kra</p> ... Show More
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Publication Date
Sun Jul 25 2021
Journal Name
Journal Of Al-qadisiyah For Computer Science And Mathematics
A Survey paper on Lossy Audio Compression Methods
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During the two last decades ago, audio compression becomes the topic of many types of research due to the importance of this field which reflecting on the storage capacity and the transmission requirement. The rapid development of the computer industry increases the demand for audio data with high quality and accordingly, there is great importance for the development of audio compression technologies, lossy and lossless are the two categories of compression. This paper aims to review the techniques of the lossy audio compression methods, summarize the importance and the uses of each method.

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